I have looked into sound issues recently and there’s only so much you can really do it seems. Street noise outside has to be blocked by something solid, not plants. Inside you can diffuse- things like brick, wood, rugs keep the sound from bouncing around and echoing. I’m going to have a music room in my new house, so I saw a few articles on internet about it. I saw some felt wall tile that looked good here on houzz. Otherwise you’d probably need an expert to add something technical like insulation.

Thanks Colleen! I'll post this here to expand on our situation as well- because it's a full renovation, we can do whatever it takes (if the numbers make sense) to insulate/add layers/build out this exterior wall, as well as select the right windows and minimize window sizes if needed as well.

It's going to be worth finding a consultant for this; strangers on the internet are only going to be so helpful for your specific use case. Some "experts" work sales for companies to peddle specific products - avoid those people. You want an independent acoustics consultant.

Basic concepts for soundproofing are: you need a lot of mass to resist sound vibration transfer. Then dead airspace and another interior wall decoupled from the exterior wall to resist any remaining low-frequency vibration. This is basically how recording studios are built (also with decoupled floors/ceilings etc etc).

There's a pretty common misconception that absorption = soundproofing; those are different things. Soft surfaces will make rooms less reverberant in the high frequencies, but doesn't block the sound itself.

Thanks so much, I'm going look into acoustics consultants in the area and go from there.

I live in a city condo and have researched, but could only go so far. Use triple pane windows, layers of window treatments including semi transparent honey comb shades for sound and privacy but allow light, Roman shades hung outside the window with blackout and inner lining. Ad soft fabric to help bounce sound around. They also make drywall for sound control or use two layers of drywall and insulation. There are also sound panels that can be added to finished walls on interior or ceiling but haven’t tried that and also tracks available for shades to keep sound from “leaking”.